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//
//
// TrackingAction.cc
// 
//
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#include "TrackingAction.hh"

#include "DetectorConstruction.hh"
#include "RunAction.hh"
#include "EventAction.hh"

#include "G4Track.hh"

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TrackingAction::TrackingAction(EventAction* EA)
:eventaction(EA)
{ }
 
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void TrackingAction::PreUserTrackingAction(const G4Track*)
{}

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void TrackingAction::PostUserTrackingAction(const G4Track* aTrack)
{
  //scattering angle of  primary particle
  if (aTrack->GetParentID() == 0 ){

    G4double theta = 0.0;
    G4double    vx = (aTrack->GetMomentumDirection()).x(); 

    if(vx <= -1.0)    { theta = -CLHEP::pi; }
    else if(vx < 1.0) { theta = std::acos(vx); }
    else { G4cout << "TrackingAction: vx - 1 = " << vx - 1 << G4endl; }
    eventaction->AddTheta(theta);   
  }
}
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